Kook Hoon, Risitano Antonio M, Zeng Weihua, Wlodarski Marcin, Lottemann Craig, Nakamura Ryotaro, Barrett John, Young Neal S, Maciejewski Jaroslaw P
Hematology Branch of the National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, USA.
Blood. 2002 May 15;99(10):3668-75. doi: 10.1182/blood.v99.10.3668.
We studied the degree and the pattern of skewing of the variable region of beta-chain (VB) T-cell receptor (TCR) repertoire in aplastic anemia (AA) at initial presentation and after immunosuppression using a high-resolution analysis of the TCR VB complementarity-determining region 3 (CDR3). Age-matched healthy individuals and multitransfused patients with non-immune-mediated hematologic diseases were used as controls. In newly diagnosed AA, the average frequency of CDR3 size distribution deviation indicative of oligoclonal T-cell proliferation was increased (44% +/- 33% vs 9% +/- 9%; P =.0001); AA patients with human leukocyte antigen (HLA)-DR2 and those with expanded paroxysmal nocturnal hemoglobinuria clones showed more skewed VB repertoires. Nonrandom oligoclonal patterns were found for VB6, VB14-16, VB21, VB23, and VB24 subfamilies in more than 50%, and for VB15, VB21, and VB24 in more than 70% of AA patients with HLA-DR2. Patients received immunosuppression with antithymocyte globulin (ATG)/cyclosporine (CsA) or cyclophosphamide (CTX) with CsA in combination, and their VB repertoire was reanalyzed after treatment. Whereas no significant change in the degree of VB skewing in patients who had received ATG was seen, patients treated with CTX showed a much higher extent of oligoclonality within all VB families, consistent with a profound and long-lasting contraction of the T-cell repertoire. VB analysis did not correlate with the lymphocyte count prior to lymphocytotoxic therapy; however, after therapy the degree of VB skewing was highly reflective of the decrease in lymphocyte numbers, suggesting iatrogenic gaps in the VB repertoire rather than the emergence of clonal dominance. Our data indicate that multiple specific clones mediate the immune process in AA.
我们使用对TCR VB互补决定区3（CDR3）的高分辨率分析，研究了再生障碍性贫血（AA）初诊时及免疫抑制后β链（VB）T细胞受体（TCR）库可变区的偏斜程度和模式。年龄匹配的健康个体和多次输血的非免疫介导血液系统疾病患者作为对照。在新诊断的AA中，指示寡克隆T细胞增殖的CDR3大小分布偏差的平均频率增加（44%±33%对9%±9%；P = 0.0001）；携带人类白细胞抗原（HLA）-DR2的AA患者和阵发性夜间血红蛋白尿克隆扩增的患者显示出更偏斜的VB库。在超过50%的携带HLA-DR2的AA患者中，发现VB6、VB14 - 16、VB21、VB23和VB24亚家族存在非随机寡克隆模式，而在超过70%的此类患者中，VB15、VB21和VB24存在该模式。患者接受抗胸腺细胞球蛋白（ATG）/环孢素（CsA）或环磷酰胺（CTX）与CsA联合的免疫抑制治疗，并在治疗后重新分析其VB库。接受ATG治疗的患者VB偏斜程度无显著变化，而接受CTX治疗的患者在所有VB家族中显示出更高程度的寡克隆性，这与T细胞库的深度和持久收缩一致。VB分析与淋巴细胞毒性治疗前的淋巴细胞计数无关；然而，治疗后VB偏斜程度高度反映淋巴细胞数量的减少，提示VB库中存在医源性缺口而非克隆优势的出现。我们的数据表明，多个特定克隆介导AA中的免疫过程。
